Html "overlay" which allows clicks to fall through to elements behind it

Ensuring interaction flows smoothly

Let the clicks flow through the overlay

By applying pointer-events: none; on the overlay, users are able to interact with the elements underneath it. To guarantee full transparency, you may also want to use:

.overlay {
  background: none !important;  /* Overlay: "I'm not even here!" */
}


Remember to test your solution across different browsers for potential inconsistencies with the pointer-events CSS property.

Managing stacking context

Overlays and underlying elements will stack according to their z-index values. An overlay with a higher z-index will appear above other elements. By combining a high z-index with pointer-events: none;, your overlay can stay in place while allowing clicks to pass through.

Balancing visual aesthetics and functionality

A semi-transparent overlay might be necessary for aesthetic reasons. Luckily, this does not hinder your ability to interact with the elements below.

.overlay {
  background-color: rgba(255, 255, 255, 0.5); /* Ghostly Presence */
  pointer-events: none;
}


Here, the overlay provides visual content but still allows for interaction with elements beneath.

Mouse events' forwarding

In more complex scenarios, you may need the overlay to capture specific events and then forward them to the underlying elements. This will require hiding the overlay momentarily to capture and refire click events.

document.querySelector('.overlay').addEventListener('click', function(e) {
  this.style.display = 'none';  // "Now you see me, now you don't!"
  let elem = document.elementFromPoint(e.clientX, e.clientY);  // Locate the element underneath 
  elem.click();  // Keep clicking!
  this.style.display = 'block';  // "I'm baaack!"
});


Handling complex interaction scenarios

Enabling multiple event types

Instead of confining yourself to just clicks, remember to test for other interactions like hover effects:

.interactive-element:hover {
  /* This is where style meets functionality! */
}
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Ensure these interactions run smoothly under the overlay. Regularly check that the event bubbling isn't hindered, fostering a consistent user experience.

Using pseudo-elements for non-blocking overlays

Creating a visually similar overlay does not always mean introducing additional HTML elements that might block interactions. Pseudo-elements (::before or ::after, for example) are great solutions:

.passthrough::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  pointer-events: none;  /* Ghost in the Shell, anyone? */
  /* Overlay styles can be added here */
}


Advanced techniques for layered interactions

To further refine this approach, consider using HTML canvases or scripting techniques to fine-tune interactions between overlay and underlying elements. Monitor mouse events to decide when to intercept or propagate these events.

References